In recent years, there has been spreading an IPTV (Internet Protocol TV) scheme for sending contents using an internet line as a transmission line. In the IPTV scheme, whole content is divided into a media packet as a unit, and a stream obtained by multiplexing these media packets is transmitted. The media packets are not always correctly transmitted from a transmitter to a receiving apparatus, and the packets may be lost.
A recovery technique such as an FEC (Forward Error Correction) encoding transmission is used to recover the lost packets. In the FEC technique, a plurality of packets are grouped, and an FEC packet is generated for each group by performing a predetermined operation and transmitted on the stream. When a packet in a group is partially lost, the receiving apparatus can recover the lost packet by performing a predetermined operation using the FEC packet. In this technique, because the receiving apparatus does not have to request the transmitter to retransmit the packet, this technique is suitable for the IPTV scheme requiring real-time processing.
In order to reduce the delay time since the receiving apparatus receives the stream until the stream is displayed on a display device, the lost packets should be efficiently recovered using the FEC packets.